1. Field of the Invention
The present invention relates to an optical device package, and more particularly to an optical device package including one or more hermetically bonded optical fibers, and a method for making same.
2. Background of the Art
Optical device packages are known in the art. Typically such packages include one or more optical fibers such as those used in communications, a housing, and means to secure the terminal portion of the optical fiber within the housing. Optical fibers are typically fabricated from fused silica or specialty glasses having very low absorption of light for wavelengths used for communications. The housing can be adapted to engage other optical devices so as to act as a connector. The optical fiber can act as a transmitter, wherein the optical signal carried by the fiber exits the end of the fiber, or a receiver, in which the end of the fiber receives a signal from an external source. Optical device assemblies can include both transmitters and receivers.
Because the optical fibers are usually of very small diameter and require a highly precise alignment, it is necessary to stabilize the position and orientation of an optical fiber in an optical device by securing it to the housing. One way of securing the optical fiber includes the use of a metal solder, e.g., tin-lead alloy, which has a melting point lower than that of the fiber. For example, U.S. Pat. No. 4,708,429 to Clark et al., which is herein incorporated by reference, discloses a method of securing the optical fiber by metallizing a portion of the length of the fiber with chromium and gold to enhance the subsequent wetting of the fiber by metal solder.
However, this method has disadvantages in that it requires the step of applying a coating of metal to the glass fiber to promote adhesion of a metal solder. This step adds to the time and cost of manufacture. It would be desirable to have a simpler method of securing a glass fiber to a housing.
A method for securing a glass fiber to a housing. The method comprises the steps of: (a) providing a housing having a wall; (b) positioning the glass fiber in proximity to the wall, the glass fiber having a non-metallized surface; (c) applying a quantity of solder glass frit to the glass fiber, the solder glass frit being in contact with both the housing wall and the non-metallized surface of the glass fiber and having a melting point below the melting point of the glass fiber; and (d) heating the solder glass frit to a temperature sufficient to at least soften the solder glass frit so as to form a seal between the non-metallized surface of the glass fiber and the housing wall.
The method herein advantageously avoids the step of metallizing the surface of the glass fiber, which would be necessary if metal solder were used instead of fiber glass frit.